scope:

This recommendation applies to industrial heated indirectly metallic heating elements (e.g., for heat-treatment, hot-forming, etc.) in which the internal atmosphere is composed of air not intentionally modified. The recommendation applies to batch chamber, bell, elevator, shaft, carriage, or to furnaces of any similar construction. These furnaces may be constructed either with or without forced air circulation. This recommendation covers furnaces of low and very low voltage categories (below 500 V). The object of this recommendation is the standardization of testing conditions and methods to determine the essential parameters and technical data of the above-mentioned furnaces.